Blood bag system and blood treatment method

ABSTRACT

A blood bag system includes: a first bag in which blood containing multiple components is stored; a second bag in which a relative medium-density component is stored; a third bag in which a relative low-density component is stored; a first tube through which the relative low-density component and the relative medium-density component are transported from the first bag to the second bag; and a second tube through which the relative low-density component is transported from the first bag to the third bag. A blood treatment method involves: centrifuging blood containing multiple components in a first bag, transporting a low-density component from the first bag to a third bag through a first tube and transporting a relative medium-density component from the first bag to the second bag through the first tube.

CROSS REFERENCES TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No. 13/467,813filed on May 9, 2012, which is a continuation of InternationalApplication No. PCT/JP2010/068808 filed on Oct. 25, 2010, and claimspriority to Japanese Application No. 2009-257118 filed on Nov. 10, 2009,the entire content of all three of which is incorporated herein byreference.

TECHNICAL FIELD

The present invention generally relates to a blood bag system and ablood treatment method for centrifuging whole blood and storingindividual blood components in respective bags.

BACKGROUND DISCUSSION

Conventionally, whole blood transfusion in which all the components ofblood obtained by blood donation are put to transfusion has been commonpractice. With the recent progress of technology, blood componenttransfusion has come to be carried out in which the blood obtained isseparated into its components such as red blood cells, platelets andplasma and only the component(s) necessary for a patient is transfusedinto the patient. Using blood component transfusion, the burden on thepatient's circulatory system and side effects can be alleviated, andgenerally effective utilization of donated blood can be achieved.

The blood (whole blood) obtained by blood donation is centrifuged to bethereby separated into a light supernatant PPP (platelet poor plasma)fraction, a heavy precipitated CRC (concentrated red cell) fraction, andbuffy coat therebetween. The buffy coat contains leukocytes, plateletsand red cells; especially, as for platelets, the proportion of youngfresh platelets is high.

In order to separate whole blood into the three blood componentsincluding platelet poor plasma, concentrated red cells and buffy coat,and further to transport the blood components into predetermined storagebags, there has hitherto been used a blood bag system configured byconnecting a plurality of bags using a plurality of tubes. An example isdisclosed in U.S. Pat. No. 6,910,998.

One conventional example of a blood bag system includes a first bag(combined buffy coat bag and whole blood bag) for storing whole blood, afirst tube connected at its one end to an upper portion of the firstbag, a second bag (plasma bag) which is connected to the other end ofthe first tube and in which platelet poor plasma is to be stored, asecond tube connected at its one end to a lower portion of the firsttube, and a third bag (red cell bag) which is connected to the other endof the second tube and in which concentrated red cells are to be stored.In order to preserve whole blood in the state of being separated intothe blood components by use of the blood bag system configured asjust-mentioned, the whole blood in the first bag is centrifuged to beseparated into platelet poor plasma, concentrated red cells and buffycoat, and, thereafter, the platelet poor plasma is transported to thesecond bag through the first tube connected to an upper portion of thefirst bag, and the concentrated red cells are transported to the thirdbag through the second tube connected to a lower portion of the firstbag.

The specification of U.S. Pat. No. 6,910,998 discloses a blood bagsystem similar to the one conventional example mentioned above.

A centrifuging and transporting apparatus which permits a step ofcentrifuging whole blood and a step of transporting blood componentsobtained by centrifugation to be performed by a single apparatus may beconfigured to include a centrifugal drum having a plurality of unitinsertion holes and driven to rotate in a circumferential direction anda plurality of insert units to be inserted in the unit insertion holes.An example is disclosed in U.S. Pat. No. 6,910,998. In this case, theinsert unit permits the above-mentioned blood bag system to be mountedthereto.

When the above-mentioned blood bag system is supposed to be mounted tothe centrifuging and transporting apparatus configured as above,difficulties can arise. A first bag in the above-mentioned blood bagsystem has a top-and-bottom (TAB) type bag structure in which a firsttube is connected to an upper portion thereof and a second tube isconnected to a lower portion thereof. Therefore, in mounting the firsttube to the above-mentioned insert unit, the second tube provided at thelower portion of the first bag must be laid around upward from the lowerside (bottom side) of the insert unit, and the handling operation isbothersome, so that it is difficult to smoothly carry out the mountingoperation. In addition, if the second tube undergoes kinking (torsion orsharp bending) due to the handling of the second tube, the second tubemay be closed, possibly making it impossible to transport bloodcomponents.

SUMMARY

The blood bag system includes: a first bag in which blood containing aplurality of components is stored; a second bag in which a relativemedium-density component obtained by centrifugation of the blood in thefirst bag is stored; a third bag in which a relative low-densitycomponent obtained by centrifugation of the blood in the first bag isstored; a first tube through which an upper portion of the first bag andan inlet of the second bag are connected and through which the relativelow-density component and the relative medium-density component aretransported from the first bag to the second bag; and a second tubethrough which an outlet of the second bag and the third bag areconnected and through which the relative low-density component istransported from the first bag to the third bag by way of the first tubeand the second bag.

The blood bag system is configured so that blood containing a pluralityof components and contained in the first bag is separated into threelayers including a relative low-density component, a relativemedium-density component and a relative high-density component, byapplying a centrifugal force to the blood, and the first bag is pressedso that the relative low-density component is transported from the firstbag to the third bag through the first tube, the second bag and thesecond tube, whereas the relative medium-density component istransported from the first bag to the second bag through the first tube.Of the blood components centrifugally separated, the relativemedium-density component is stored in the second bag, whereas therelative low-density component is stored in the third bag, and theremaining relative high-density component is stored in the first bag.Consequently, the blood can be separated into the relative low-densitycomponent, relative the medium-density component and the relativehigh-density components, and these components can be preserved in therespective bags. The first tube through which the relativemedium-density component and the relative low-density component aretransported from the first bag to the second bag and the third bag isconnected to the upper portion of the first bag, so that a tube to beconnected to a lower portion of the first bag is unnecessary (i.e.,there are no tubes connected to the lower portion of the first bag), andtubes are connected only to the upper portion of the first bag in thisconfiguration. Accordingly, the bag configuration is simplified so thatconvenience for the user to use a blood bag system is enhanced. Inaddition, since handling of tubes in mounting the blood bag system to acentrifuging and transporting apparatus is facilitated, the mounting ofthe system to the centrifuging and transporting apparatus becomes easyto carry out. Since the second bag is used only for storage of therelative medium-density component and its capacity may be set accordingto the amount of the relative medium-density component to be storedtherein, the second bag can be reduced in size, as compared with arelative medium-density component bag according to the related art.Consequently, in the case where the relative medium-density component isbuffy coat, it is possible to reduce the amount of buffy coat left inthe second bag, and to enhance platelet recovery late, at the time ofpreparing a platelet preparation by buffy coat pooling conducted as asubsequent step.

The second bag can be configured such that the cross-sectional area of achannel at the outlet is smaller than the cross-sectional area of achannel at the inlet. The rate of flow into the third bag is thussuppressed, whereby the medium-density component can be inhibited orprevented from flowing into the third bag.

The blood bag system can also include a first clamp by which the firsttube is closed and opened; and a second clamp by which the second tubeis closed and opened. With this arrangement, upon detecting the transferof a predetermined component into the first tube at the time oftransporting the relative low-density component and the relativemedium-density component from the first bag to the second bag, thesecond clamp is operated to close the second tube, whereby thepredetermined component is prevented from flowing into the third bag. Inaddition, with the first tube closed by operating the first clamp whenthe first bag has been pressed by a predetermined amount, it is possibleto collect a predetermined amount of a blood component into the secondbag and to prevent the relative high-density component from flowing intothe second bag.

The blood bag system can also include a fourth bag configured to store arelative high-density component transported from the first bag. Thesystem can also include a filter disposed between the first bag and thefourth bag and by which predetermined cells are removed, a third tubethrough which an upper portion of the first bag and an inlet of thefilter are connected and through which the relative high-densitycomponent is transported from the first bag to the filter, and a fourthtube through which an outlet of the filter and the fourth bag areconnected and through which the relative high-density component istransported from the filter to the fourth bag. It is thus possible tofilter the relative high-density component left in the first bag by thefilter to thereby remove predetermined cells and to store in the fourthbag the relative high-density component freed of the predeterminedcells. In addition, since the third tube interconnects the first bag andthe filter is connected to the upper portion of the first bag, a tubeconnected to a lower portion of the first bag is unnecessary, and tubesare connected only to the upper portion of the first bag in thisconfiguration. Accordingly, even in the configuration in which thefilter is provided, it is relatively easy to lay around the tubes inmounting the blood bag system to a centrifuging and transportingapparatus and, hence, it is rather easy to mount the blood bag system tothe centrifuging and transporting apparatus.

The blood containing the plurality of components is preferably wholeblood, and the relative low-density component, the relativemedium-density component and the relative high-density component areplasma, buffy coat and concentrated red cells, respectively.

Another aspect of the disclosure here involves a blood treatment methodcomprising centrifuging blood containing a plurality of components intoa relative low-density component, relative a medium-density componentand a relative high-density component in a first bag, and transportingthe relative low-density component from the first bag to a third bagthrough a first tube connected to an upper portion of the first bag andtransporting the relative medium-density component from the first bag toa second bag provided between the first bag and the third bag throughthe first tube, by pressing the first bag.

The pressing of the first bag is performed to cause the relativelow-density component and the relative medium-density component to flowout from the first bag through the first tube in the order of therelative low-density component and the relative medium-densitycomponent, wherein the relative low-density component is transportedfrom the first bag to the third bag through the second bag and a secondtube connected to an outlet of the second bag, and the relativemedium-density component is transported to the second bag through thefirst tube.

The relative medium-density component is stored in the second bag,whereas the relative low-density component is stored in the third bag,and the remaining relative high-density component is stored in the firstbag. The tubes are connected only to the upper portion of the first bagand so the convenience in use of the blood bag system is enhancedthrough simplification of the bag configuration, and handling of thetubes at the time of mounting the blood bag system to a centrifuging andtransporting apparatus is facilitated, whereby the mounting of thesystem to the centrifuging and transporting apparatus is facilitated.Also, the second bag can be reduced in size, as compared with a relativemedium-density component bag according to the related art. In the casewhere the relative medium-density component is buffy coat, therefore,the amount of the buffy coat left in the second bag at the time ofpreparing a platelet preparation by buffy coat pooling can be reduced,and platelet recovery rate can be enhanced.

While transporting the relative low-density component and the relativemedium-density component from the first bag to the second bag, the kindof a solution flowing through the first tube is detected, and a channelin the second tube is closed upon detection of transfer of the relativemedium-density component into the first tube. The relativemedium-density component is thus prevented from flowing into the thirdbag.

During the separation or transporting, a channel in the first tube isclosed when the first bag has been pressed by a predetermined amount. Itis thus possible to collect a predetermined amount of a blood componentinto the second bag and to inhibit or prevent the relative high-densitycomponent from flowing into the second bag.

The blood treatment method also includes transporting, after theseparation step, the relative high-density component left in the firstbag from the first bag to a filter by which predetermined cells areremoved, through a third tube connected to an upper portion of the firstbag, and transporting the relative high-density component passed throughthe filter from the filter to a fourth bag. Because the third tube isconnected to the upper portion of the first bag, a tube connected to alower portion of the first bag is unnecessary, and tubes are connectedonly to the upper portion of the first bag in this configuration.Accordingly, even in the configuration wherein the filter is provided,it is rather easy to lay around the tubes at the time of mounting to ablood bag system for use in the blood treatment method to a centrifugingand transporting apparatus, and it is also relatively easy to mount theblood bag system to the centrifuging and transporting apparatus.

The blood with which the method is performed is whole blood, and therelative low-density component, the relative medium-density componentand the relative high-density component are plasma, buffy coat andconcentrated red cells, respectively.

Another aspect of the disclosure involves a blood bag system comprising:a first bag possessing an interior surrounded configured to store bloodcontaining a plurality of components including a relative medium-densitycomponent and a relative low-density component, with the first bagpossessing a top wall, an oppositely disposed bottom wall, and twooppositely positioned side walls each extending between the top wall andthe bottom wall, the top wall of the first bag including a throughopening which opens to the interior of the first bag; a second bagpossessing an interior configured to store the relative medium-densitycomponent obtained by centrifugation of the blood in the first bag, withthe second bag including an inlet in fluid communication with theinterior of the second bag and an outlet in fluid communication with theinterior of the second bag; and a third bag possessing an interiorconfigured to store the relative low-density component obtained bycentrifugation of the blood in the first bag. A first tube possesses afirst end connected to the top wall of the first bag so that the firsttube is fluidly communicatable with the interior of the first bag by wayof the through opening in the top wall of the first bag and possesses asecond end connected to the inlet of the second bag to permit therelative low-density component and the relative medium-density componentin the interior of the first bag to be transported to the interior ofthe second bag. A second tube possesses a first end connected to theoutlet of the second bag and a second end connected to the third bag topermit the relative low-density component in the interior of the firstbag to be transported to the interior of the third bag by way of thefirst tube and the second bag.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view of a blood bag system according to one embodimentdisclosed here by way of example.

FIG. 2 is a perspective view of a centrifuging and transportingapparatus.

FIG. 3 is a partial enlarged perspective view of a centrifugal drum inthe centrifuging and transporting apparatus.

FIG. 4 is an exploded perspective view of an insert unit.

FIG. 5 is a schematic illustration of a condition in which a first tubeand a second tube in the blood bag system according to the oneembodiment disclosed here by way of example, are held by a tube holderof the centrifuging and transporting apparatus.

FIG. 6 is a partly omitted enlarged plan view showing a first clampoperating part in the blood bag system according to the one embodimentdisclosed here by way of example and the surroundings thereof.

FIG. 7 is an illustration of operation of the centrifuging andtransporting apparatus.

FIG. 8 is an illustration of buffy coat pooling.

DETAILED DESCRIPTION

A blood bag system 10 and a blood treatment method will be describedbelow by reference to embodiments disclosed as examples and whilereferring to the accompanying drawings.

The blood bag system 10 illustrated in FIG. 1 is for centrifuging wholeblood containing a plurality of components into three components, namelya low-density component (relative low-density component), amedium-density component (relative medium-density component) and ahigh-density component (relative high-density component) (in thisembodiment, whole blood is centrifuged into three components includingplasma, buffy coat and concentrated red cells), and containing andpreserving the components separately in different bags.

As shown in FIG. 1, the blood bag system 10 includes: a first bag 12 inwhich blood containing a plurality of components is contained; a secondbag 14 in which a medium-density component obtained by centrifuging theblood in the first bag 12 is stored; a third bag 16 in which alow-density component obtained by centrifuging the blood in the firstbag 12 is contained; a first tube 18 through which an upper portion ofthe first bag 12 and an inlet 13 of the second bag 14 are connected andthrough which the low-density component and the medium-density componentare transported from the first bag 12 to the second bag 14; and a secondtube 20 by which an outlet 15 of the second bag 14 and the third bag 16are connected and through which the low-density component is transportedfrom the first bag 12 to the third bag 16 by way of the first tube 18and the second bag 14.

The first bag 12, the second bag 14 and the third bag 16 are eachfabricated by a method in which flexible sheet materials made of aflexible resin such as polyvinyl chloride and polyolefin are placed oneach other and are fused (by heat fusing or high-frequency fusing) oradhered to each other at peripheral sheet portions into a bag form. Afirst flow blood bag 32 and a red cell bag 38 which will be describedlater are also configured in a bag form.

In the illustrated embodiment disclosed as an example, the bags 12, 16,38 are configured to include two oppositely positioned sides eachextending between the top and the bottom of the bag. The tube 18intersects the top of the bag 12, 16, 38 and the lumen of the tube isthus communicatable with the interior of the first bag 12. Similarly,the tube 20 intersects the top of the third bag 16 and the lumen in thetube 20 is thus in fluid communication with the interior of the thirdbag 16. The same is also true with respect to the tube connected to thetop of the red cell bag 38.

The first bag 12 is a bag for containing (storing) blood (whole blood)collected from a donor. Hereafter, the first bag 12 will be referred toas the “blood collection bag.” The blood collection bag 12 is configuredto contain the whole blood at the time of blood collection. After thewhole blood is centrifuged and buffy coat is transported to the secondbag 14 while the plasma is transported to the third bag 16 as will bedescribed later, the blood collection bag 12 is used for containing andpreserving the unfiltered concentrated red cells which are the remainingcomponent. In other words, the blood collection bag 12 serves both as awhole blood containing bag and as an unfiltered concentrated red cellcontaining bag.

Preferably, an anticoagulant is preliminarily contained in the bloodcollection bag 12. The anticoagulant is normally a solution, andexamples thereof include ACD-A solution, CPD solution, CPDA-1 solution,and heparin sodium solution. The proper amount of anticoagulant isprepared corresponding to the amount of blood to be collected.

One end of a blood collection tube (proximal-side blood collection tube)22 is connected to an upper portion of the blood collection bag 12. Aclamp 23 by which a lumen in the blood collection tube 22 is closed andopened is provided at an intermediate portion of the blood collectiontube 22. One end of a sealing member (breaking communication member) 24is connected to the other end of the blood collection tube 22. Thesealing member 24 is so configured as to close the channel in an initialcondition and to open the channel by a breaking operation.

Such a sealing member 24 as this includes a tube formed, for example,from a flexible resin such as vinyl chloride, and a tubular body whichis connected to the inside of the tube in a liquid-tight manner, isclosed at one end thereof and has a brittle part at a portion in thelongitudinal direction thereof. To put the sealing member 24 into anopen (communicating) state, the tubular body is bent from the outside ofthe tube by fingers or the like to thereby break the brittle part.Consequently, a channel in the tube which has been closed by the tubularbody is opened, whereby the sealing member 24 is put into an open state.

To the other end of the sealing member 24 is connected a first port 26 aof a branch connector 26. To a second port 26 b of the branch connector26 is connected one end of a blood collection tube (distal-side bloodcollection tube) 28, and to the other end of the blood collection tube28 is connected a blood collection needle 29. Before use, a cap 27 a ismounted in covering relation to the blood collection needle 29, and,after use, a needle guard 27 b is mounted to the blood collection needle29. The needle guard 27 b is so disposed as to be movable along thelongitudinal direction of the blood collection tube 28.

To a third port 26 c of the branch connector 26 is connected one end ofa branch tube 30. At an intermediate portion of the branch tube 30 isprovided a clamp 31 by which a channel in the branch tube 30 is closedand opened. To the other end of the branch tube 30 is connected a firstflow blood bag 32. At the time of collecting blood from a donor, a firstflow (collected blood first flow) of the blood collected is firstcontained into the first flow blood bag 32 in a predetermined amount,before containing the blood into the blood collection bag 12. In thiscase, while the sealing member 24 is kept in a closed state (initialstate), the clamp 31 is put into an open state, whereby the collectedblood first flow is inhibited from flowing to the blood collection tube22 side, namely, to the blood collection bag 12 side. At the same time,the collected blood first flow can be led into the first flow blood bag32 through the blood collection tube 28, the branch connector 26 and thebranch tube 30.

A sampling port 34 is connected to the first flow blood bag 32, and, byattaching a blood collection tube to the sampling port 34, the collectedblood first flow is sampled into the blood collection tube. Thecollected blood first flow thus sampled serves as blood for testing.Depending on the use, the part ranging from the branch connector 26 tothe sampling port 34 may be omitted.

The second bag 14 is a bag to contain (store) buffy coat (BC).Hereafter, the second bag 14 will be referred to as the “BC bag.” The BCbag 14 has a bag structure of a top-and-bottom (TAB) form wherein theinlet 13 is provided at one end and the outlet 15 is provided at theother end. The BC bag 14 is so set as to have a necessary and sufficientcapacity, taking into account the amount of buffy coat to be collected;though the capacity is smaller than the capacity of the blood collectionbag 12.

The third bag 16 is a bag in which to contain (store) and preserveplasma. Hereafter, the third bag 16 will be referred to as the “plasmabag.”

The first tube 18 is connected to an upper portion of the bloodcollection bag 12. In the present embodiment, a sealing member 17 isprovided at that end portion of the first tube 18 which is located onthe blood collection bag 12 side. The sealing member 17 has the sameconfiguration and function as those of the above-mentioned sealingmember 24. In addition, a first clamp 19 by which a channel in the firsttube 18 is closed and opened is provided at an intermediate portion ofthe first tube 18.

The second tube 20 is connected at its one end to the outlet 15 of theBC bag 14, and is connected at its other end to the plasma bag 16. Asecond clamp 21 by which a channel in the second tube 20 is closed andopened is provided at an intermediate portion of the second tube 20.

As shown in FIG. 1, the blood bag system according to this embodimentfurther includes a fourth bag (hereafter referred to as the “red cellbag”) 38 into which to contain (store) and preserve concentrated redcells transported from the blood collection bag 12, a filter 36 which isdisposed between the blood collection bag 12 and the red cell bag 38 andby which predetermined cells are removed, a third tube 40 by which anupper portion of the blood collection bag 12 and an inlet of the filter36 are connected, and a fourth tube 42 through which an outlet of thefilter 36 and the red cell bag 38 are connected. In the presentembodiment, the filter 36 is configured as a leukocyte removal filter.

A clamp 43 by which a channel in the third tube 40 is closed and openedis provided at an intermediate portion of the third tube 40. A clamp 44by which a channel in the fourth tube 42 is closed and opened isprovided at an intermediate portion of the fourth tube 42.

Each of the tubes (inclusive of the first tube 18 and the second tube20) in the blood bag system 10 is a tube made of a transparent flexibleresin and a lumen extending between opposite ends of the tube. Each ofthe clamps (inclusive of the first clamp 19 and the second clamp 21) maybe a standard product that has been used conventionally. In addition, itis recommendable to preliminarily color the clamps separately indifferent colors according to the locations of use and the intendeduses. At the time of sterilization and during stock before use of theblood bag system 10, each of the clamps is in an open state and theinside of each of the bags is in a communicating and uniform sterilizedstate.

The blood bag system 10 according to the present embodiment can be used,for example, in the state of being mounted to a centrifuging andtransporting apparatus (automatic centrifugal separator) 50 as shown inFIG. 2. This centrifuging and transporting apparatus 50 is used fordividing whole blood contained in the blood collection bag 12 into threelayers (components) including plasma, buffy coat and concentrated redcells, transporting the buffy coat to the BC bag 14, while transportingthe plasma to the plasma bag 16, and leaving the concentrated red cellsin the blood collection bag 12.

For ease in understanding the method for using the blood bag system 10disclosed here, the configuration of the centrifuging and transportingapparatus 50 will be described below. In the following description, thedirection of arrows A will be referred to as the radial direction, andthe direction of arrows B as the circumferential direction. Thecircumferential direction is strictly the direction along the circulararc as indicated by arrows B, but, for convenience of description, thedirection orthogonal to arrows A at a location being described will alsobe referred to as the circumferential direction.

As shown in FIG. 2, the centrifuging and transporting apparatus 50 isbox-shaped, and includes an openable/closable cover 52 at the top, acentrifugal drum (centrifuging means for centrifuging) 53 in the inside,six unit insertion holes 54 provided at regular angular (60°) intervalsinside the centrifugal drum 53, six insert units 56 inserted inrespective ones of the unit insertion holes, and six pushers (pressingmeans) 66 (see FIG. 3) which are provided at a central region and whichcan each be advanced and retracted in the rotational radial directionrelative to each insert unit 56. The centrifuging and transportingapparatus 50 is operated based on operations on a console section 62provided at the front surface thereof, is controlled by a microcomputer,and is configured to display predetermined information on a monitor 64.

As shown in FIG. 3, a central body 53 a of the centrifugal drum 53 has aholding lever 67 biased by an elastic body to hold an end portion of atube holder 80 (described later), electrodes 68, first rods 72 andsecond rods 74, and the pusher 66. The first rods 72 and the second rods74, provided in two pairs, are driven to advance and retract in theradial direction A. The rods on the side of a first circumferentialdirection B1 constitute a first clamp driving means 76 a for opening andclosing the first clamp 19 (see FIG. 1), while the rods on the side of asecond circumferential direction B2 constitute a second clamp drivingmeans 76 b for opening and closing the second clamp 21 (see FIG. 1). Thepart shown in FIG. 3 may be configured as a unit, and six such units maybe combined in the circumferential direction.

FIG. 4 is an exploded perspective view of the insert unit 56 as viewedfrom the inside diameter side (inside diameter direction A2). As shownin FIG. 4, the insert unit 56 has a unit main body 58, and a cover body60. The unit main body 58 is a bottomed tube (a tube with a bottom wallso that the bottom is closed) which has a wide arcuate shape in top planview and is open at the top, wherein a small chamber (first chamber) 94on the inside diameter side and a large chamber (second chamber) 95 onthe outside diameter side are partitioned from each other by an arcuatewall 93. The small chamber 94 is opening not only at the top but also onthe inside diameter side. At an upper portion on the inside diameterside of the small chamber 94, there is provided the tube holder 80 whichis plate-shaped and projects to the inside diameter side.

The tube holder 80 has a first guide path 82 for guiding the first tube18, a second guide path 84 for guiding the second tube 20, and two pins83 provided at an end portion in the outside diameter direction A1. Eachof the first guide path 82 and the second guide path 84 has a grooveshape formed by providing walls on both side along the whole lengththereof and is opening on the upper side.

The first guide path 82 extends in the inside diameter direction A2 froma nearly central part of an end portion in the outside diameterdirection A1 of the tube holder 80, is bent to the first circumferentialdirection B1 at an intermediate part in the radial direction A, andreaches an outer end of the tube holder 80. A first clamp holding part86 for holding the first clamp 19 is provided at that portion of thefirst guide path 82 which forms a groove along the circumferentialdirection B.

The second guide path 84 extends in the inside diameter direction A2from that part near the center of an end portion in the outside diameterdirection A1 of the tube holder 80 and on the second circumferentialdirection B2 side relative to the first guide path 82, is bent to thesecond circumferential direction B1 at an intermediate part in theradial direction A, and reaches an outer end of the tube holder 80. Asecond clamp holding part 88 for holding the second clamp 21 is providedat that portion of the second guide path 84 which forms a groove alongthe circumferential direction B.

The tube holder 80 further has a first clamp operating part 90 foroperating the first clamp 19 into a closed state and an open state, anda second clamp operating part 91 for operating the second clamp 21 intoa closed state and an open state.

The cover body 60 is a cover mounted on the unit main body 58 from theouter side, is configured to cover the outer side, the upper side andthe lower side of the unit main body 58, and securely holds the bloodbag system 10 mounted to the unit main body 58.

FIG. 5 is a schematic illustration of a condition in which the firsttube 18 and the second tube 20 are held by the tube holder 80. Inaddition, in FIG. 5, for easy understanding, a part of the bloodcollection bag 12 whose upper portion is fixed by the two pins 83 of thetube holder 80 is depicted by imaginary lines; part of the first tube 18and the second tube 20, the BC bag 14, and the plasma bag 16 are alsoshown in simplified form, and the other parts of the blood bag system 10are omitted in the drawing.

As shown in FIG. 5, the blood collection bag 12 is fixed at an upperportion thereof to the tube holder 80 by a method in which the two pins83, 83 provided on the tube holder 80 are inserted in two holes 12 a, 12a (see FIG. 1) provided in the upper portion of the blood collection bag12. The first tube 18 is mounted and held in the first guide path 82 ofthe tube holder 80. In addition, the first clamp 19 provided on thefirst tube 18 is held by the first clamp holding part 86.

The BC bag 14 connected to the other end of the first tube 18 iscontained in the large chamber 95 (see FIG. 4). The second tube 20connected to the outlet of the BC bag 14 is laid around to the tubeholder 80, and is mounted and held in the second guide path 84 of thetube holder 80. The second clamp 21 provided on the second tube 20 isheld by the second clamp holding part 88.

The plasma bag 16 connected to the other end of the second tube 20 iscontained in the large chamber 95 (see FIG. 4). While the third tube 40,the filter 36, the fourth tube 42 and the red cell bag 38 are notspecifically illustrated in FIG. 5, they are contained in the largechamber 95. The blood collection tubes 22, 28, the branch tube 30 andthe first flow blood bag 32 and the like are cut off after anti-leakagesealing by welding the blood collection tube 22 by a tube sealer or thelike, after blood is collected into the blood collection bag 12 andbefore mounting the blood bag system 10 to the centrifuging andtransporting apparatus 50.

As shown in FIG. 5, the tube holder 80 further has a sensor 97 fordetecting the kind of liquid passing inside the first tube 18 at aposition on the upstream side of the first clamp 19. The sensor 97includes a light casting part 98 and a light receiving part 99, and thekind of liquid passing these parts can be determined based on the degreeof light transmission through the liquid. A plurality of contacts incontinuity with the sensor 97 or an interface circuit thereof areprovided at a lower surface of the tube holder 80, and these contactsare set in contact with the reception-side electrodes 68 (see FIG. 3)provided on the central body 53 a of the centrifugal drum 53, whereby asignal from the sensor 97 can be supplied to the microcomputer.

FIG. 6 shows a first clamp operating part 90 and the surroundings of thefirst clamp operating part 90. As shown in FIG. 6, the first clamp 19 isa resin-made member which has a flattened C-shape as a whole, isprovided at its one end with a pressing part 106 for pressing the firsttube 18, is provided at its other end with a latch part 108 forengagement with the pressing part 106, is provided with a projected part110 at a position opposed to the pressing part 106, and is provided atboth sides in the longitudinal direction with holes in which the firsttube 18 is inserted (through which the first tube 18 passes). The secondclamp 21 and the other clamps also have the same structure as the firstclamp 19.

With the pressing part 106 pushed into the inner side, the first tube 18is pinched by an inside projection of the pressing part 106 and theprojected part 110, whereby the channel in the first tube 18 can beclosed, and the pressing part 106 is held in the state of being engagedwith the latch part 108. When the latch part 108 is displaced toward theouter side starting from the condition where the pressing part 106 isheld by the latch part 108, the latch part 108 and the pressing part 106are disengaged from each other and the pressing part 106 is displacedtoward the outer side, whereby the channel in the first tube 18 isopened.

As shown in FIG. 6, the first clamp operating part 90 has a firstpressing body 101 which is swung by operation of the first rod 72 so asto push in the pressing part 106, and a second pressing part 102 whichis swung by operation of the second rod 74 so as to tilt the latch part108. The first pressing body 101 and the second pressing body 102 arerotatably supported on the tube holder 80 through shaft parts 103, 104,respectively, and are biased in a direction away from the pressing part106 and the latch part 108 by springs; in addition, they are soconfigured as to be displaced toward the side of the pressing part 106and the latch part 108 against biasing forces of the springs whenpressed by the first rod 72 and the second rod 74, respectively.

In the first clamp operating part 90 configured as above, with the firstrod 72 and the second rod 74 driven to be advanced and retracted, thepressing part 106 and the latch part 108 of the first clamp 19 can beoperated, whereby the channel in the first tube 18 can be closed andopened. The second clamp operating part 91 is symmetrical in shape withthe first clamp operating part 90.

The blood bag system 10 according to the present embodiment is basicallyconfigured as above-described, and its operation and effect will bedescribed below.

Reference is first made to FIG. 1. At the time of collecting blood froma donor, first, the collected blood first flow is sampled into the firstflow blood bag 32, as mentioned above. After sampling of the collectedblood first flow is completed, the branch tube 30 is closed by the clamp31, and the above-mentioned breaking operation is applied to the sealingmember 24, to put the channel in the blood collection tube 22 into anopen state. In this instance, the clamp 23 is set in an open state,whereas the sealing member 17 is set in the initial state (closedstate). As a result, the blood from the donor flows into the bloodcollection bag 12 by way of the blood collection tubes 28, 22. When apredetermined amount of the blood is collected and stored into the bloodcollection bag 12, the blood collection tube 22 is closed by the clamp23 so that the blood (whole blood) in the blood collection bag 12 willnot flow out. Then, as described above, the blood collection tube 22 iswelded and sealed by the tube sealer or the like, followed by cuttingoff the blood collection tube 22 at the sealed portion.

Next, in order to separate the whole blood collected into the blood bagsystem 10 into plasma, buffy coat and concentrated red cells and storethem respectively in predetermined bags, the blood bag system 10 ismounted to the centrifuging and transporting apparatus 50. At the timeof the mounting, first, the channels in the first tube 18 and the secondtube 20 are put into a closed state by the first clamp 19 and the secondclamp 21, and thereafter the above-mentioned breaking operation isapplied to the sealing member 17, to set the channel therein in an openstate.

Then, as shown in FIG. 5, the first tube 18 and the second tube 20 areheld on the tube holder 80, and the blood collection bag 12 is containedinto the small chamber 94 (see FIG. 4) of the unit main body 58, withits upper portion fixed on the tube holder 80. The part ranging from theBC bag 14, the plasma bag 16 and the third tube 40 to the red cell bag38 is contained into the large chamber 95 (see FIG. 4) of the unit mainbody 58. In this case, it is recommendable to contain the BC bag 14 andthe plasma bag 16 in the large chamber 95 in a non-bent state (see FIG.7) so that in the separation step after the centrifugation step, thebuffy coat and the plasma smoothly flow respectively into the BC bag 14and the plasma bag 16, to be stored there. As for the filter 36 and thered cell bag 38, they are not used in the centrifugation step and thesubsequent separation step; therefore, it is recommendable to containthem in the large chamber 95 after making them compact by, for example,rounding or bending, whereby a space in which to contain the BC bag 14and the plasma bag 16 can be secured. After the blood bag system 10 ismounted to and contained in the unit main body 58, the cover body 60 ismounted to the unit main body 58, thereby putting the insert unit 56into an assembled state.

Subsequently, as shown in FIG. 2, the insert unit 56 each with the bloodbag system 10 contained therein are inserted into the unit insertionhole 54 in the centrifuging and transporting apparatus 50. As a result,end portions of the tube holders 80 are fixed by the holding levers 67.In addition, the contacts of the sensors or the interface circuitstherefor are set in contact with the electrodes 68 (see FIG. 3).Basically, six insert units 56 are mounted to the centrifuging andtransporting apparatus 50. However, not more than five insert units 6(preferably, three or two insert units at regular angular intervals) maybe mounted, insofar as they are well-balanced.

Next, the cover 52 of the centrifuging and transporting apparatus 50 isclosed, and thereafter the console section 62 is operated, whereby thecentrifugation step and the separation step are performed automatically.

In the automatic operation of the centrifuging and transportingapparatus 50, first, the centrifugal drum 53 is rotated to perform thecentrifugation step. In this instance, the first clamp 19 and the secondclamp 21 are preliminarily closed. For attaining further certainty,however, the first rod 72 is once extended and the first clamp 19 is putinto a closed state by the pressing part 106. The second clamp 21 isalso set into a closed state.

In the centrifugation step, as shown in FIG. 7, a centrifugal force isexerted on the whole blood stored in the blood collection bag 12 insidethe small chamber 94, whereby concentrated red cell 114 as ahigh-density component is transferred to the outside diameter direction,plasma 112 as a low-density component is transferred to the insidediameter direction, and buffy coat 113 as a medium-density component ismoved to an intermediate region; thus, the whole blood is separated intothree layers.

The centrifuging and transporting apparatus 50 starts the separationstep after the centrifugation step. In the separation step, whilekeeping the rotation of the centrifugal drum 53, the first clamp drivingmeans 76 a and the second clamp driving means 76 b are operated to putthe channels in the first tube 18 and the second tube 20 into an openstate.

Subsequently, as shown in FIG. 7, the pusher 66 is displaced in thecentrifugal direction A1 to press the blood collection bag 12. The bloodcollection bag 12 is reduced in volume by being clamped between thepusher 66 and a wall, so that the liquid contained therein is dischargedvia the first tube 18. In this instance, since the first tube 18 isoriented to the inside diameter side, the plasma 112 located most on theinside diameter side flows out of the blood collection bag 12, and flowsthrough the first tube 18, the BC bag 14 and the second tube 20 into theplasma bag 16.

After flowing of the plasma 112 out of the blood collection bag 12 isfinished, the buffy coat 113 next starts flowing out of the bloodcollection bag 12. In this instance, when the flow of the red cells (thered cells contained in the buffy coat) in the first tube 18 is detectedby the sensor 97 (see FIG. 5), the channel in the second tube 20 isclosed by the second clamp 21, whereby the buffy coat 113 is inhibitedfrom flowing into the plasma bag 16. The flow of the red cells in thefirst tube 18 can be confirmed by the sensor 97, based on thetransparency (in other words, the turbidity) of the liquid flowing inthe first tube 18.

As shown in FIG. 7, the BC bag 14 has a structure wherein thecross-sectional area of a channel at the outlet 15 is set to be smallerthan the cross-sectional area of a channel at the inlet 13. This settingproduces a flow rate difference which helps ensure that a liquidaccumulation of a certain amount of the plasma 112 is formed in the BCbag 14, whereby the rate of flow of liquid into the plasma bag 16 can berestrained from becoming excessively high. Therefore, although a certaintime lag exists after detection of the red cells by the sensor 97 untilthe closing of the second tube 20 by the second clamp 21, it ispossible, by suppressing the flowing-in rate into the plasma bag 16through the provision of the flow rate difference as above-mentioned, tosecurely inhibit or prevent the buffy coat 113 from flowing into theplasma bag 16. The structure of the BC bag 14 in which thecross-sectional area at the outlet 15 is set smaller than thecross-sectional area at the inlet 13 may be replaced by a structure inwhich the cross-sectional area of the channel in the second tube 20 isset smaller than the cross-sectional area of the channel in the firsttube 18, over the whole length of or at a part of the second tube 20.

When the pusher 66 is further advanced and the blood collection bag 12is pressed by a predetermined amount (a predetermined amount of thebuffy coat in the BC bag 14 is collected), the pusher 66 is stopped, andthe first clamp driving means 76 a is operated to close the channel inthe first tube 18 by the first clamp 19.

When the separation step as above is finished, the blood bag system 10is taken out of the insert unit 56. Further, the first tube 18 and thesecond tube 20 in the blood bag system 10 are welded and sealed,followed by cutting, whereby each of the bags is cut off.

As above-described, according to the blood bag system 10 in the presentembodiment disclosed as an example, a centrifugal force is exerted onthe whole blood contained in the blood collection bag 12 to separate thewhole blood into the three layers of the plasma 112, the buffy coat 113and the concentrated red cells 114. Then, the blood collection bag 12 ispressed in the thickness direction thereof, whereby the plasma and thebuffy coat are transported from the blood collection bag 12 to the BCbag 14 through the first tube 18, and the plasma 112 is transported fromthe second bag 14 to the plasma bag 16 through the second tube 20. Thishelps ensure that, of the blood components centrifugally separated, thebuffy coat is stored in the BC bag 14, whereas the plasma 112 is storedin the plasma bag 16, and the concentrated red cells 114 as a residueare left stored in the blood collection bag 12. Consequently, the wholeblood is separated into the plasma 112, the buffy coat 113 and theconcentrated red cells 114, which are separated (collected) into therespective bags.

In the blood bag system 10 disclosed here, the first tube 18 fortransporting the plasma 112 and the buffy coat 113 from the bloodcollection bag 12 to the BC bag 14 and the plasma bag 16 is connected toan upper portion of the blood collection bag 12. Therefore, a tube to beconnected to a lower portion of the blood collection bag 12 isunnecessary, and the tubes are connected only to the upper portion ofthe blood collection bag 12 in this configuration. Accordingly, the bagconfiguration is simplified, so that the convenience for the user inusing the blood bag system 10 is enhanced. In addition, handling of thetubes in mounting the blood bag system 10 to the centrifuging andtransporting apparatus 50 is facilitated, so that the mounting to thecentrifuging and transporting apparatus 50 is facilitated.

As for the concentrated red cells 114 left in the blood collection bag12, leukocytes can be removed therefrom through filtration by the filter36, and the concentrated red cells 114 freed of the leukocytes can bestored in the red cell bag 38. In addition, since the third tube 40through which the blood collection bag 12 and the filter 36 areconnected is connected to an upper portion of the blood collection bag12, a tube to be connected to a lower portion of the blood collectionbag 12 is unnecessary. Thus, the blood collection bag 12 has atop-and-top (TAT) type bag structure in which the tubes are connectedonly to the upper portion of the bag. Consequently, in spite of theconfiguration in which the filter 36 is provided, handling of the tubesat the time of mounting the blood bag system 10 to the centrifuging andtransporting apparatus 50 is relatively easy to perform, so that themounting to the centrifuging and transporting apparatus 50 is easy tocarry out.

The BC bag 14 is used only for storing the buffy coat, and its capacitymay be set according to the amount of the buffy coat to be storedtherein. This permits a reduction in size of the BC bag 14, as comparedwith a conventional buffy coat bag. Consequently, the amount of thebuffy coat left in the BC bag 14 at the time of preparing a plateletpreparation by the buffy coat pooling conducted as the subsequent stepcan be reduced, and the platelet recovery rate can be thereby enhanced.

Now, description will be made of “buffy coat pooling” (hereinafterreferred to as BC pooling) which is a treatment wherein the contents ofa plurality of BC bags 14 containing the buffy coat obtained by theabove-mentioned treatment are transported and collected into a singlebag. As shown in FIG. 8, in the BC pooling, a plurality of the BC bags14 are connected in series, by use of respective tube joining devices,to a tube 126 connected to a BC pooling bag 120. In the BC bags 14, thebuffy coat obtained by the above-mentioned treatment is contained. Inaddition, a clamp 132 is in a closed state.

Next, to a tube of the BC bag 14 at a terminal end, a storage solutionbag 123 containing a platelet storage solution is connected by use of atube joining device. Thereafter, the storage solution bag 123 is hungfrom a hanger (not shown), and the clamp 132 is opened to open a channelbetween a branch connector 124 and the BC pooling bag 120, whereby thebuffy coat is collected from the BC bags 14 into the BC pooling bag 120.In this instance, platelets are left adhering to inside walls of the BCbags 14. Therefore, the buffy coat in the BC bags 14 is washed away inthe following manner.

A breaking operation is applied to a sealing member 130 of the storagesolution bag 123 to open a channel, whereby the platelet storagesolution is transported into the BC bags 14, and the buffy coatremaining in the BC bags 14 is mixed with the platelet storage solutionand moved into the BC pooling bag 120. Thereafter, a tube 122 is weldedat a part near the BC pooling bag 120 by use of a tube sealer or thelike, to be thereby sealed in a leak-free manner, and is cut.

Here, in the BC pooling as above-mentioned, the BC bags 14 can beconnected in parallel with each other. In that case, the BC bags 14 areconnected respectively to a plurality of tubes branched from the tube126, and the storage solution bags 123 are connected to the tubes 122branched from the tube 126 by branch connectors 124, whereby BC poolingis conducted. In the case where the BC bags 14 are connected in serieswith each other as shown in FIG. 8, however, the platelet storagesolution is moved sequentially into the plurality of BC bags 14, so thatthe platelets adhering inside the BC bags 14 can be effectively washedaway by a simple operation. Therefore, buffy coat recover rate isenhanced, with the result that the recovery rate of the plateletsobtained by centrifugation of the buffy coat can be enhanced.

In addition, while the plurality of BC bags 14 must each be providedwith ports at an upper portion and a lower portion thereof in order tobe connected in series with each other, the BC bag 14 in the blood bagsystem 10 according to the present invention is convenient for adoptionof a series connection mode in BC pooling, since the BC bag 14 has atop-and-bottom (TAB) type bag structure wherein it is provided with theinlet 13 and the outlet 15 as above-mentioned.

To the BC pooling bag 120 is connected another tube 134, and to aterminal end of this tube 134 are sequentially connected a leukocyteremoval filter and a platelet storage bag. After the BC pooling, thebuffy coat in the BC pooling bag 120 is centrifugally separated into asupernatant liquid and a precipitated liquid, and the supernatant liquidthus obtained is transported to the platelet storage bag through theabove-mentioned leukocyte removal filter. The centrifugation step andthe separation step in this case may be carried out by use of theabove-mentioned centrifuging and transporting apparatus 50.

While a treatment for centrifuging whole blood into three components ofplasma, buffy coat and concentrated red cells has been described in thepresent embodiment, the present invention is not limited to this. Forexample, the invention may be applied to a treatment in which bloodobtained by preliminarily removing leukocytes is centrifugally separatedinto three components including a low-density component, amedium-density component and a high-density component, that is, threecomponents including plasma (leukocyte-freed plasma), concentratedplatelets (leukocyte-freed concentrated platelets) and concentrated redcells (leukocyte-freed concentrated red cells).

The detailed description above describes a blood bag system and bloodtreatment method. The inventions here are not limited, however, to theprecise embodiments and variations described above and illustrated inthe drawing figures. Various changes, modifications and equivalentscould be effected by one skilled in the art without departing from thespirit and scope of the invention as defined in the appended claims. Itis expressly intended that all such changes, modifications andequivalents which fall within the scope of the claims are embraced bythe claims.

What is claimed is:
 1. A blood treatment method comprising: centrifugingblood containing a plurality of components and located in a first bag toseparate the blood into a relative low-density component, a relativemedium-density component and a relative high-density component in thefirst bag; transporting the relative low-density component from thefirst bag to a third bag through a first tube which opens into an upperportion of the first bag by pressing the first bag; and transporting therelative medium-density component from the first bag to a second bagprovided fluidly between the first bag and the third bag through thefirst tube by pressing the first bag.
 2. The blood treatment methodaccording to claim 1, wherein: the pressing of the first bag totransport the relative low-density component and the relativemedium-density component causes the relative low-density component tofirst flow out of the first bag through the first tube while therelative medium-density component remains in the first bag; the relativelow-density component is transported to the third bag by first passingthrough the first tube, next passing through the second bag and thennext passing through a second tube connected to an outlet of the secondbag; and the relative medium-density component is transported to thesecond bag through the first tube only after the relative low-densitycomponent has been transported to the second bag.
 3. The blood treatmentmethod according to claim 2, further comprising detecting, during thetransporting of the relative low-density component and themedium-density component through the first tube from the first bag tothe second bag, whether the component in the first tube is the relativelow-density component or the relative medium-density component, andclosing the second tube when it is detected that the component in thefirst tube is the relative medium-density component.
 4. The bloodtreatment method according to claim 1, further comprising closing thefirst tube to stop the transport of the relative low-density componentand the relative medium-density component when the first bag has beenpressed by a predetermined amount.
 5. The blood treatment methodaccording to claim 1, further comprising: transporting, after thetransporting of the relative low-density component to the third bag andthe transporting of the relative medium-density component to the secondbag, the relative high-density component remaining in the first bag fromthe first bag to a filter by which predetermined cells are removed,through a third tube connected to an upper portion of the first bag, andtransporting the relative high-density component passed through thefilter from the filter to a fourth bag.
 6. The blood treatment methodaccording to claim 1, wherein the blood containing the plurality ofcomponents is whole blood, and the relative low-density component, therelative medium-density component and the relative high-densitycomponent are plasma, buffy coat and concentrated red cells,respectively.